Statistics Flashcards
What is prevalence?
number of cases in a defined population at a single point in time and is expressed as a decimal or a percentage.
What is sensitivity?
percentage of true positives
what is specificity
percentage of true negatives (e.g. 90% specificity = 90% of people who do not have the target disease will test negative).
How to read a CTG?
DR C BRAVADO
Define Risk
Contractions
Bra: baseline rate
variability
Accelerations
decelerations
overall impression
What is fetal tachycardia?
baseline hr greater than 160 bpm
What is the baseline rate of fetal heart on ctg?
The baseline rate is the average heart rate of the fetus within a 10-minute window.
Causes of fetal tachycardia (5)
Fetal hypoxia
Chorioamnionitis
Hyperthyroidism
Fetal or maternal anaemia
Fetal tachyarrhythmia
What is fetal bradycardia?
Less than 110bpm
Causes of fetal bradycardia (5)
Prolonged cord compression
Cord prolapse
Epidural and spinal anaesthesia
Maternal seizures
Rapid fetal descent
Reduced variability on ctg can be caused by? (6)
Fetal sleeping: this should last no longer than 40 minutes (this is the most common cause)
Fetal acidosis (due to hypoxia): more likely if late decelerations are also present
Fetal tachycardia
Drugs: opiates, benzodiazepines, methyldopa and magnesium sulphate
Prematurity: variability is reduced at earlier gestation (<28 weeks)
Congenital heart abnormalities
Accelerations with uterine contractions on ctg is a sign of?
Healthy Fetus
How does Type 1 Resp failure present?
Hypoxaemia Pa02 <8kpa with Normocapnia (Pac02 <6kpa)
How does Type 2 Resp Failure present?
Hypoxemia Pa02 <8kpa with Hypercapnia Pac02 >6kpa
Name 3 causes of Type 1 Resp Failure/VQ Mismatch?
Pulmonary Oedema
Bronchoconstriction
Pulmonary Embolism
Name 7 causes of Type 2 Resp Failure with Hypoventilation?
COPD
Pneumonia
Rib Fractures
Obesity
Guillan Barre
Motor Neurone Disease
Opiates
What makes an ABG ph ACIDIC?
<7.35